Adaptable digital pen and touch sensitive device

ABSTRACT

Methods and apparatuses are provided that address interoperability limitations of current digital pens and touch sensitive devices. In aspects, methods are provided for operating an adaptable digital pen and touch sensitive device to determine the best means for pen state information such as pressure information to be transferred from the pen to the device. A digital pen includes multiple communication interfaces to permit wide compatibility with touch sensitive devices. A communication interface is provided that enables the digital pen to communicate via an active pen protocol with a digitizer of the touch sensitive device while operating in a first mode. Another communication interface is provided as an alternative channel for communicating pen state information to the touch sensitive device while operating in a second mode. Where neither such interface suffices for communicating pen state information to the touch sensitive device, the digital pen may operate in a reflective capacitive mode.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/119,406, filed Aug. 31, 2018, the entirety of which is incorporatedby reference herein.

BACKGROUND

Writing and drawing with pencils, crayons or markers and the like,continues to be one of the earliest skills people achieve, and use ofpencils and pens in everyday life is ubiquitous. The advent of touchsensitive screens, graphic tablets, digital art boards, and similarinput devices for computers and mobile devices created and sustainsdemand for specialized tools that mimic ordinary pencils and pens whenused with such devices. That is, there is a demand for pen-like devicesspecially designed for use with touch sensitive input devices, and thatgreatly enhance the precision and “feel” of the device when used towrite or draw on such input devices. These pen-like devices aretypically referred to as digital or active pens.

A typical digital pen must be used in combination with a compatibletouch sensitive input device, such as a tablet, that includes digitizerand other circuitry and programming necessary for the input device toquickly and accurately determine information about the state of the pen.Such information may include the location of the digital pen on thetablet face, the amount pressure being applied by the user, and the tiltangle of the digital pen and other information. Unfortunately, thecircuitry and programming required for a digital pen and tablet tofunction together is usually proprietary to a particular company ormanufacturer. Simply put: not all digital pens are compatible with alltablets.

The lack of compatibility has at least a few consequences. For one,consumers often accidentally buy a digital pen that is incompatible withtheir tablet despite extensive efforts to label the digital penpackaging properly. This problem is exacerbated by the breakneck pace oftechnological advancement whereby new products including touch sensitivescreens are coming to market near constantly. The market is likewisebeing hit with many digital pens for these new devices, many of whichare not compatible with devices only one or two years old. Thus, themarketplace for pens is confusing, and the lack of universal oradaptable devices results in obsolescence. Moreover, many people usemultiple touch sensitive devices at work and at home on any given day,but adaptable digital pens are not available to use with some or all ofsuch devices.

SUMMARY

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used to limit the scope of the claimed subject matter.

Methods and apparatuses are provided that address limitations of currentdigital pens and touch sensitive devices inasmuch as many such pens anddevices are incapable of interoperating. In aspects, methods areprovided for operating an adaptable digital pen to determine the bestmeans for the adaptable digital pen to communicate with a touchsensitive device to permit pen state information to be transferredthereto. In other aspects, methods are provided for operating a touchsensitive device to similarly determine the best means to communicatewith a digital pen to permit receipt of pen state information therefrom.In embodiments, methods are provided to operate the digital pen or touchsensitive device in a reflective capacitive mode or as a capacitivetouch sensitive device, respectively, and without sending or receivingpen state information, where other methods are unable to determine howto send or receive, respectively, pen state information. In otheraspects an adaptable digital pen is provided, and embodiments areconfigured to determine the best means for the adaptable digital pen tocommunicate with a touch sensitive device to permit pen stateinformation to be transferred thereto.

In one implementation, a digital pen is enabled to determine whether atouch sensitive device is enabled to receive pen state information via afirst communication channel while operating in a first mode, and if so,operating the digital pen in a first mode. Where the digital pen isunable to make such a determination or where it is determined that thetouch sensitive device is not enabled to receive pen state informationvia the first communication channel, embodiments of the digital pen areenabled to switch the digital pen to a second operating mode anddetermine whether the touch sensitive device is enabled to receive penstate information via a second communication channel. If the touchsensitive device is so enabled, the digital pen continues to operate inthe second operating mode. Otherwise, in embodiments, the digital pen isenabled to operate in as a reflective capacitive digital pen, and notsend pen state information to the touch sensitive device.

In another implementation, a touch sensitive device is enabled todetermine whether the touch sensitive device is receiving pen stateinformation from a digital pen via a first communication channel whileoperating in a first mode, and if so, operating the touch sensitivedevice in a first mode. Where the touch sensitive device is unable tomake such determination, or where it is determined that the touchsensitive device is not enabled to receive pen state information via afirst communication channel, embodiments of the touch sensitive deviceare enabled to switch the touch sensitive device to the second operatingmode, and determine whether the touch sensitive device is enabled toreceive pen state information from a digital pen via a secondcommunication channel. If the touch sensitive device is so enabled, thetouch sensitive device continues to operate in the second operatingmode. Otherwise, in embodiments, the touch sensitive device is enabledto operate as a capacitive touch sensitive device, and not receive penstate information from a digital pen.

Further features and advantages of the invention, as well as thestructure and operation of various embodiments, are described in detailbelow with reference to the accompanying drawings. It is noted that theembodiments are not limited to the specific embodiments describedherein. Such embodiments are presented herein for illustrative purposesonly. Additional embodiments will be apparent to persons skilled in therelevant art(s) based on the teachings contained herein.

BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES

The accompanying drawings, which are incorporated herein and form a partof the specification, illustrate embodiments of the present applicationand, together with the description, further serve to explain theprinciples of the embodiments and to enable a person skilled in thepertinent art to make and use the embodiments.

FIG. 1 shows a block diagram of an adaptable digital pen and touchsensitive device system, according to an example embodiment.

FIG. 2 shows an adaptable digital pen, according to an exampleembodiment.

FIG. 3 shows a touch sensitive device, according to an exampleembodiment.

FIG. 4 shows a flowchart of a process for determining whether to operatean adaptable digital pen with a touch sensitive device in a first modeor a second mode, according to an embodiment.

FIG. 5 shows a flowchart of a process for determining whether a touchsensitive device is receiving pen state information from a digital penvia a first communication channel while operating in a first mode,according to an embodiment.

FIG. 6 shows a flowchart of a process for determining that an adaptabledigital pen cannot be configured to operate with a touch sensitivedevice in either a first mode or a second mode, according to an exampleembodiment.

FIG. 7 shows a flowchart of a process for determining whether to operatea touch sensitive device with a digital pen in a first mode or secondmode, according to an embodiment.

FIG. 8 shows a flowchart of a process for determining whether a touchsensitive device is receiving pen state information from a digital penvia a first communication channel while operating the touch sensitivedevice in a first mode, according to an embodiment.

FIG. 9 shows a flowchart of a process for determining that a touchsensitive device cannot be configured to operate with a digital pen ineither a first mode or a second mode, according to an exampleembodiment.

FIG. 10 is a block diagram of an example processor-based computer systemthat may be used to implement various embodiments.

The features and advantages of the present invention will become moreapparent from the detailed description set forth below when taken inconjunction with the drawings, in which like reference charactersidentify corresponding elements throughout. In the drawings, likereference numbers generally indicate identical, functionally similar,and/or structurally similar elements. The drawing in which an elementfirst appears is indicated by the leftmost digit(s) in the correspondingreference number.

DETAILED DESCRIPTION I. Introduction

The present specification and accompanying drawings disclose one or moreembodiments that incorporate the features of the present invention. Thescope of the present invention is not limited to the disclosedembodiments. The disclosed embodiments merely exemplify the presentinvention, and modified versions of the disclosed embodiments are alsoencompassed by the present invention. Embodiments of the presentinvention are defined by the claims appended hereto.

References in the specification to “one embodiment,” “an embodiment,”“an example embodiment,” etc., indicate that the embodiment describedmay include a particular feature, structure, or characteristic, butevery embodiment may not necessarily include the particular feature,structure, or characteristic. Moreover, such phrases are not necessarilyreferring to the same embodiment. Further, when a feature, structure, orcharacteristic is described in connection with an embodiment, it issubmitted that it is within the knowledge of one skilled in the art toeffect such feature, structure, or characteristic in connection withother embodiments whether or not explicitly described.

Numerous exemplary embodiments of the present invention are described asfollows. It is noted that any section/subsection headings providedherein are not intended to be limiting. Embodiments are describedthroughout this document, and any type of embodiment may be includedunder any section/subsection. Furthermore, embodiments disclosed in anysection/subsection may be combined with any other embodiments describedin the same section/subsection and/or a different section/subsection inany manner.

II. Example Embodiments.

Embodiments are configured to allow flexible and adaptable operation ofdigital pens and touch sensitive devices. Touch sensitive devicesgenerally include a digitizer for detecting touch input from a finger ordigital pen. Digitizers typically operate in one of two modes. Forexample, digitizers in mobile touch sensitive devices such as smartphones and tablets generally operate in a capacitive multi-touch modeusing capacitive sensors. One such type of sensor is called a ‘mutualcapacitive’ sensor that is typically formed as a matrix includingtransparent conductive material (e.g. Indium Tin Oxide [ITO]) arrangedin parallel rows and columns, with a capacitor node created where therows and columns overlap, deposited in layers over the top of the activepixel layers (e.g. LED, OLED or LCD layers) of a touch sensitivedisplay. Touching the surface of the touch sensitive display with afinger or other conductive object induces a change in the charge storagecapacity, and hence capacitance, of the capacitor nodes (i.e.,overlapping layers) in the vicinity of the touch. Each capacitive nodeis associated with one or more pixels of the display screen that areimmediately below the contact point on the screen. The change incapacitance of the capacitor nodes may be detected to determine touchlocation of the finger or conductive object on the touch sensitivedisplay. The capacitance change may be detected by rapidly sampling eachnode by any of a variety of techniques as is known in the art. Mutualcapacitive detection allows multi-touch operation where multiple touchobjects (e.g., fingers) can be tracked at the same time.

Digitizers that include mutual capacitive sensors may, within certainlimits, function to accept touch input with anything capable of inducinga capacitance change in the sensors with perhaps the most familiarexample being, a user's finger. Another example includes what is oftenreferred to as a passive stylus. A passive stylus typically includes arelatively large, flexible and blunt tip that is internally electricallyconnected to the shaft of the stylus that is itself conductive. Whenheld in the hand, the stylus becomes essentially an electrical extensionof the hand, acting as an artificial finger that may be used as onewould a pen. One problem with this type of stylus is that there arelimits to how small you can construct the tip and expect it to functionproperly with touch sensitive devices. If the tip is too small, it maynot be capable of changing sensor node capacitance enough to properly beread out (i.e., input may appear as noise and be filtered out as such).A large, flexible tip may offer all the precision needed for simplynavigating menus on the device or webpages. Such a tip is generally not,however, precise enough to use for art drawings or much else. It is alsodifficult or impossible to see the contact point of the stylus on thetouch sensitive leading to further inaccuracy. To address these andother shortcomings of a passive stylus, other types of digital pen havebeen created.

One type of digital pen operates in a mode generally known as“reflective capacitive.” As discussed above, the act of touching acapacitive sensor based digitizer induces a change in the charge storedin capacitor nodes of the digitizer at the touch point. It is also thecase, however, that this action also induces a change in the chargestored at the tip electrode of, for example, a digital pen. A reflectivecapacitive digital pen operates to detect and measure the inducedcurrent or voltage change at the tip electrode, and then amplify thatchange in response. The result is additional capacitance change at thecapacitor nodes due to the amplification, and therefore a much strongertouch signal being detected by the digitizer. Because of theamplification, it is possible to produce a digital pen with a muchsmaller and rigid tip that may provide the digitizer with higher spatialresolution.

Another type of digital pen operates in a manner similar to a reflectivecapacitive digital pen but may include the ability to communicateinformation directly to the touch sensitive device itself and may alsoinclude specifically engineered tip electrode characteristics designedto work with a matching digitizer design. This type of digital pen isgenerally known as a “active digital pen.” Such active digital pens andtheir matching digitizers may feature excellent spatial resolutiondesirable by, for example, graphic designers and artists. Moreover, theability to establish one-way communication from digital pen to thedigitizer, or two-communication between them, permits additionalinformation to be collected by the digitizer, and provided to hostapplications running on, for example, the counterpart touch sensitivedevice.

Embodiments of an adaptable digital pen disclosed herein below areenabled to automatically switch the digital pen between one of threemodes of operation depending on the operating requirements of aparticular touch sensitive device: a reflective capacitive operatingmode, or one of two types of active pen operating modes.

For example, FIG. 1 shows a block diagram of an adaptable digital penand touch sensitive device system 100, according to an exampleembodiment. System 100 includes a touch sensitive device 110 and anadaptable digital pen 102 enabled to send pen state information 108 totouch sensitive device 110. Adaptable digital pen 102 includes sensor(s)106, a pen shaft 116, a pen tip 112 and a tip electrode 114. Touchsensitive device 110 includes a digitizer 104. These features of system100 are described as follows.

Adaptable digital pen 102 is a digital pen adapted to function withmyriad touch sensitive devices such as, for example, touch sensitivedevice 110. As discussed in greater detail below, embodiments ofadaptable digital pen 102 may be enabled to gather pen state information108 such as, for example, pressure data from a pressure sensor includedin sensor(s) 106 and determine a means by which adaptable digital pen102 can be enabled to communicate pen state information 108 to touchsensitive device 110. In embodiments, pen state information 108 mayinclude many types of information related to an operating state ofadaptable digital pen 102. For example, pen state information 108 mayinclude pressure sensor information, pen identifier information,timestamp information, tilt angle information, information based on astate of at least one inertial sensor, or information based on a stateat least one button of digital pen 102.

Pressure sensor information may comprise information that reflects anamount of pressure or force being exerted on pen tip 112 of adaptabledigital pen 102. As discussed above, such information may be useful forapplications to vary a rendering of digital ink in, for example, agraphic design application.

Pen identifier information may include any type of information that maybe used by touch sensitive device 110, or an application runningthereon, to configure the operation touch sensitive device 110, or theapplication. For example, in an embodiment, touch sensitive device 110may include a configurable digitizer 104 capable of exhibiting differentoperating properties, depending on an exact make and model of adaptabledigital pen 102, as reflected in the pen identifier information includedin pen state information 108.

As will be discussed in more detail below, timestamp information may beuseful for touch sensitive device 110 to correlate received pen stateinformation 108 with corresponding touch input as detected by digitizer104 of touch sensitive device 110.

In an embodiment, adaptable digital pen 102 may be configured to providetilt angle information as part of pen state information 108. Tilt angleinformation may comprise any information that reflects or can be used tocompute an angle adaptable digital pen 102 is making with a surface oftouch sensitive device 110. For example, tilt angle information mayinclude information related to tilt angle as measured by one or moresolid-state sensors of sensor(s) 106 such as a solid-state inclinometeror solid-state accelerometer. Where touch sensitive device 110 alsoincludes hardware capable of measuring a tilt angle of touch sensitivedevice 110 relative to the ground, tilt angle information received fromadaptable digital pen 102 as part of pen state information 108 may beused to compute the angle adaptable digital pen 102 is making with thesurface of touch sensitive device 110.

Although not shown in FIG. 1 , embodiments of adaptable digital pen 102may also include one or more buttons disposed on pen shaft 116 or at itsend opposite pen tip 112. Such buttons may be configured to performpredetermined functions when pressed, such as enabling an eraser mode,or functioning as a right-click in a user interface of touch sensitivedevice 110, and information related to the state of such buttons may berelayed to touch sensitive device 110 as part of pen state information108.

In one embodiment, adaptable digital pen 102 may be configured tocommunicate with touch sensitive device 110 via a first communicationinterface. In an embodiment, the first communication interface maycomprise a radio frequency (RF) communication interface using an activepen protocol. In an embodiment, tip electrode 114 may act as an antennafor transmitting RF signals wirelessly to touch sensitive device 110,where such signals may be received and decoded by digitizer 104according to the active pen protocol. In other embodiments, however,adaptable digital pen 102 may include a separate antenna configured tocouple adaptable digital pen 102 to touch sensitive device 110wirelessly via an RF connection. In either case, embodiments ofadaptable digital pen 102 also include a second communication interfaceseparate from the first communication interface for attempting toestablish a communication channel between adaptable digital pen 102 andtouch sensitive device 110. In an embodiment, the second communicationinterface may comprise a Bluetooth interface. The purpose of the secondcommunication interface is to permit adaptable digital pen 102 to bemore widely compatible with a number of different makes and models oftouch sensitive devices 110.

For example, touch sensitive device 110 may not be capable of receivingpen state information 108 via a direct RF connection between adaptabledigital pen 102 and digitizer 104 of touch sensitive device 110. Asdiscussed in more detail below, embodiments of touch sensitive device110 may therefore be configured to communicate pen state information 108via an alternative communication interface, such as, for example, aBluetooth interface. In the event adaptable digital pen 102 is incapableof communicating pen state information one way to touch sensitive device110 via either, for example, the active pen protocol RF communicationinterface, or the Bluetooth interface, adaptable digital pen 102 may beconfigured to operate as a reflective capacitive digital pen, and nottransmit pen state information 108. Note that foregoing generaldescription of the operation of system 100 is provided for illustrationonly, and embodiments of system 100 may comprise different hardwareand/or software and may operate in manners different than describedabove.

System 100 of FIG. 1 is now further described with respect to exampleembodiments. In particular, each of adaptable digital pen 102 and touchsensitive device 110 shall be described in further detail herein belowwhile describing FIGS. 2 and 3 , respectively.

In an embodiment, adaptable digital pen 102 is a digital pen that isenabled to operate in various modes to adapt its operation to therequirements of various compatible touch sensitive devices. Note, aswill be discussed in more detail below, such compatible touch sensitivedevices need not include embodiments of touch sensitive device 110 asshown in FIG. 3 . Instead, embodiments of adaptable digital pen 102 areenabled to attempt to determine an operating mode for adaptable digitalpen 102 that may be compatible with any touch sensitive device, and tooperate adaptable digital pen 102 in the determined mode. Embodiments ofadaptable digital pen 102 may comprise various hardware configurations.

For example, FIG. 2 shows an adaptable digital pen 102 according to anexample embodiment. Adaptable digital pen 102 of FIG. 2 includes penshaft 116 where first communication interface 202, second communicationinterface 204, communication decision module 206 and sensor(s) 106 maybe located. One end of pen shaft 116 includes pen tip 112 that itselfincludes tip electrode 114. In an embodiment, first communicationinterface 202, second communication interface 204, and sensor(s) 106 arecoupled to communication decision module 206. Communication decisionmodule 206 is in turn coupled to tip electrode 114. A description of anembodiment of adaptable digital pen 102 in operation will now bediscussed in conjunction with the discussion of flowchart 400 of FIG. 4.

FIG. 4 shows a flowchart 400 of a process for determining whether tooperate adaptable digital pen 102 of FIG. 2 with a touch sensitivedevice in a first mode or a second mode, according to an embodiment. Inthis context, and as explained in further detail below, operatingadaptable digital pen 102 in a first mode comprises: operating tipelectrode 114 with active pen protocol output characteristics,intermittently collecting pen state information 108, and transmittingsame to touch sensitive device 110 via first communication interface 202of FIG. 2 . Likewise, operating adaptable digital pen 102 in a secondmode comprises: operating tip electrode 114 with reflective capacitiveoutput characteristics, intermittently collecting pen state information108, and transmitting same to touch sensitive device 110 via secondcommunication interface 204 of FIG. 2 .

In an embodiment, the process of flowchart 400 may be performed bycommunication decision module 206 of adaptable digital pen 102. Note,however, that in other embodiments, one or more steps of flowchart 400may be performed by other modules or components of adaptable digital pen102. For instance, any operations described hereinafter as beingperformed by communication decision module 206 may be integrated intoone or more other modules. For example, in an embodiment, firstcommunication interface 202, second communication interface 204, andcommunication decision module 206 may be incorporated into a singlemodule. Flowchart 400 is described with continued reference to FIG. 2 .However, other structural and operational embodiments will be apparentto persons skilled in the relevant art(s) based on the followingdiscussion regarding flowchart 400 and adaptable digital pen 102 of FIG.2 .

Flowchart 400 begins with step 402. Step 402 determines whether a touchsensitive device is enabled to receive pen state information from adigital pen via a first communication channel while operating thedigital pen in a first mode. For example, as shown in FIG. 1 ,communication decision module 206 of adaptable digital pen 102 may beconfigured to determine whether touch sensitive device 110 is enabled toreceive pen state information 108 from adaptable digital pen 102 via thecommunication channel associated with first communication interface 202of FIG. 2 . In an embodiment, adaptable digital pen 102 may beconfigured to operate in a first mode, whereby pen state information 108is transmitted using first communication interface 202 as shown in FIG.2 . As discussed above, first communication interface 202 may comprisean RF communication interface adapted to operate in the first mode byusing an active pen protocol to communicate directly with digitizer 104of touch sensitive device 110, as is known in the art. In otherembodiments, however, first communication interface 202 may comprise anytype of wireless communication interface that may or may not be adaptedto use an active pen protocol and that may or may not communicatedirectly with digitizer 104.

In embodiments, communication decision module 206 may determine whethertouch sensitive device 110 is enabled to receive pen state information108 via first communication interface 202 by continually transmittingaccording to an active pen protocol while listening for returncommunication from touch sensitive device 110 that is compliant with theactive pen protocol being employed. In another embodiment, adaptabledigital pen 102 may be capable of communicating via first communicationinterface 202 using any of a number of different active pen protocolsand may attempt to establish communication with touch sensitive device110 by trying each different active pen protocol in turn until one suchactive pen protocol works, or until such time as every active penprotocol has been attempted, and no response was received. Inembodiments, communication decision module 206 is configured todetermine that touch sensitive device 110 is enabled to receive penstate information 108 upon successful receipt of return communicationfrom touch sensitive device 110 via first communication interface 202.

Flowchart 400 continues with step 404. At step 404, in response todetermining that the touch sensitive device is enabled to receive thepen state information via the first communication channel, embodimentswill continue to operate adaptable digital pen 102 in the first mode.For example, when communication decision module 206 of adaptable digitalpen 102 determines that touch sensitive device 110 is enabled to receivepen state information 108 while operating in the first mode,communication decision module 206 will continue to operate adaptabledigital pen 102 in the first mode since operating in the first mode willsuffice for delivering pen state information 108 to touch sensitivedevice 110.

Flowchart 400 continues with step 406. At step 406, in response todetermining that the touch sensitive device is not enabled to receivethe pen state information via the first communication channel, thedigital pen is switched to operate in a second mode, and it isdetermined whether the touch sensitive device is enabled to receive thepen state information from the digital pen via a second communicationchannel. For example, and with reference to FIG. 1 , communicationdecision module 206 may be configured to operate adaptable digital pen102 in a second mode, and to determine whether touch sensitive device110 is enabled to receive pen state information 108 from adaptabledigital pen 102 via the communication channel associated with secondcommunication interface 204 of FIG. 2 . In an embodiment, communicationdecision module 206 may be configured to operate adaptable digital pen102 in a second mode, whereby pen state information 108 is transmittedusing second communication interface 204 as shown in FIG. 2 . Asdiscussed above, second communication interface 204 may comprise aBluetooth communication interface adapted to operate in the second modeto communicate pen state information 108 to touch sensitive device 110.It will be understood, however, that second communication interface 204need not comprise a Bluetooth communication interface, which is merelyexemplary. In other embodiments, second communication interface 204 maycomprise any type of wireless communication interface adapted forcommunication between adaptable digital pen 102 and touch sensitivedevice 110.

In embodiments, communication decision module 206 of adaptable digitalpen 102 may determine whether touch sensitive device 110 is enabled toreceive pen state information 108 via second communication interface 204by attempting to establish communication with touch sensitive device 110using, for example, a pre-determined protocol operating over Bluetooth.Such a protocol may or may not function like an active pen protocol asknown in the art, but instead may function in any manner capable offacilitating the exchange of information between adaptable digital pen102 and touch sensitive device 110. In another embodiment, communicationdecision module 206 may be enabled to communicate via secondcommunication interface 204 using any of a number of different protocolsthat may be compatible with proprietary Bluetooth protocols associatedwith touch sensitive devices 110 from different manufacturers.Embodiments of communication decision module 206 of adaptable digitalpen 102 may attempt to establish communication with touch sensitivedevice 110 by trying each such protocol in turn until one such Bluetoothprotocol works, or until such time as an attempt has been made withevery protocol, and no response was received. In embodiments,communication decision module 206 of adaptable digital pen 102 isconfigured to determine that touch sensitive device 110 is enabled toreceive pen state information 108 upon successful receipt of returncommunication from touch sensitive device 110 via second communicationinterface 204.

Flowchart 400 concludes with step 408. At step 408, in response todetermining that the touch sensitive device is enabled to receive thepen state information via the second communication channel, the digitalpen continues to operate in the second mode. For example, whencommunication decision module 206 determines that touch sensitive device110 is enabled to receive pen state information 108 while operatingadaptable digital pen 102 in the second mode, communication decisionmodule 206 will continue to operate adaptable digital pen 102 in thesecond mode since operating in the second mode will suffice fordelivering pen state information 108 to touch sensitive device 110.

In the foregoing discussion of steps 402-408 of flowchart 400, it shouldalso be understood that at times, such steps may be performed in adifferent order or even contemporaneously with other steps. For example,in embodiments, steps 402 and 404 pertaining to operating in a firstmode, steps 406 and 408 pertaining to operating in a second mode couldbe done in the reverse order. Likewise, determining whether a touchsensitive device is enabled to receive pen state information via firstor second communication channels, as performed in steps 402 and 406, maybe performed simultaneously in some embodiments. Other operationalembodiments will be apparent to persons skilled in the relevant art(s).Note also that the foregoing general description of the operation ofadaptable digital pen 102 is provided for illustration only, andembodiments of adaptable digital pen 102 may comprise different hardwareand/or software and may operate in manners different than describedabove.

As discussed above, touch sensitive devices may receive pen stateinformation from adaptable digital pen 102 via a first communicationchannel in different ways, and embodiments of adaptable digital pen 102may be configured to determine the proper manner in which to do so. Forexample, FIG. 5 shows a flowchart 500 of a process for determiningwhether a touch sensitive device is receiving pen state information froma digital pen via a first communication channel while operating in afirst mode, according to an embodiment. Flowchart 500 is described withcontinued reference to FIG. 2 . However, other structural andoperational embodiments will be apparent to persons skilled in therelevant art(s) based on the following discussion regarding flowchart500 and adaptable digital pen 102 of FIG. 2 .

Flowchart 500 begins with step 502. Step 502 attempts to establishtwo-way communication with the touch sensitive device through the firstcommunication channel while operating the digital pen in the first mode,and when the attempt is successful, continues to operate the digital penin the first mode. For example, and as discussed above in relation toflowchart 400 of FIG. 4 , embodiments of communication decision module206 of adaptable digital pen 102 may be configured to determine whethertouch sensitive device 110 is enabled to receive pen state information108 from adaptable digital pen 102 while operating in a first mode byattempting to establish two-way communication between adaptable digitalpen 102 and touch sensitive device 110 via the communication channelassociated with first communication interface 202. More specifically,communication decision module 206 may be configured to operate adaptabledigital pen 102 in a first mode to attempt to establish two-waycommunication with touch sensitive device 110 via first communicationinterface 202 by trying each of a number of different active penprotocols to determine whether two-way communication may be establishedwith any of them. Also as discussed above, such an attempt is successfulwhen adaptable digital pen 102 successfully receives returncommunication from touch sensitive device 110 via first communicationinterface 202 and, as a result, embodiments of adaptable digital pen 102continue to operate in the first mode.

Flowchart 500 continues with step 504. At step 504, when the attempt toestablish two-way communication with the touch sensitive device throughthe first communication channel is not successful, an attempt is made toestablish two-way communication with the touch sensitive device throughthe second communication channel. For example, even though adaptabledigital pen 102 may not have succeeded in establishing two-waycommunication with touch sensitive device 110 through firstcommunication interface 202, it may be possible for embodiments ofadaptable digital pen 102 to establish one-way communication with touchsensitive device 110 through first communication interface 202. Prior todoing so, however, communication decision module 206 of adaptabledigital pen 102 must attempt to establish two-way communication withtouch sensitive device 110 via second communication interface 204 in themanner described above in relation to flowchart 400.

Flowchart 500 continues at step 506. At step 506, when the attempt toestablish two-way communication with the touch sensitive device throughthe second communication channel is successful, it is determined throughthe second communication channel whether the touch sensitive device isenabled to receive one-way communication of the pen state informationfrom the digital pen via the first communication channel. For example,communication decision module 206 of adaptable digital pen 102 may beconfigured to determine through second communication interface 204whether touch sensitive device 110 is enabled to receive one-waycommunication of pen state information 108 via first communicationinterface 202. A two-way communication channel via second communicationinterface 204 is necessary for adaptable digital pen 102 to learn fromtouch sensitive device 110 that pen state information 108 sent byadaptable digital pen 102 via first communication interface 202 is, infact, being received by touch sensitive device 110, and that adaptabledigital pen 102 should continue to send pen state information 108 viafirst communication interface 202.

Flowchart 500 continues at step 508. At step 508, when it is determinedthat the touch sensitive device is enabled to receive one-waycommunication of pen state information via the first communicationchannel, the digital pen continues to operate in the first mode. Forexample, after successfully establishing two-way communication withtouch sensitive device 110 through second communication interface 204,touch sensitive device 110 may then communicate to adaptable digital pen102 that touch sensitive device 110 is, in fact, receiving pen stateinformation 108. In response, communication decision module 206 operatesadaptable digital pen 102 and the first mode. Furthermore, adaptabledigital pen 102 may also shut down second communication interface 204,or set it to a low power mode, in an embodiment. Such power savings ispossible since pen state information 108 will continue to be transferredto touch sensitive device 110 via first communication interface 202, andsecond communication interface 204 may be used sparingly if at all.

In the foregoing discussion of steps 502-508 of flowchart 500, it shouldalso be understood that at times, such steps may be performed in adifferent order or even contemporaneously with other steps. Otheroperational embodiments will be apparent to persons skilled in therelevant art(s).

Of course, and as discussed above, it will not always be possible forembodiments of adaptable digital pen 102 to establish communication witha touch sensitive device in either the first mode or the second mode,thereby enabling it to transfer pen state information to the touchsensitive device. In such instances, embodiments may be configured tooperate in a “generic” mode that may allow adaptable digital pen 102 tofunction as an input device with the touch sensitive device in question.For example, FIG. 6 shows a flowchart 600 of a process for determiningthat an adaptable digital pen cannot be configured to operate with atouch sensitive device in either a first mode or a second mode,according to an example embodiment. Flowchart 600 is described withcontinued reference to FIG. 2 . However, other structural andoperational embodiments will be apparent to persons skilled in therelevant art(s) based on the following discussion regarding flowchart600 and adaptable digital pen 102 of FIG. 2 .

Flowchart 600 begins with step 602. In step 602, when it is determinedthat the touch sensitive device is not enabled to receive pen stateinformation via the second communication channel or when the attempt toestablish two-way communication with the touch sensitive device throughthe second communication channel is not successful, the digital pen isoperated by operating the pen tip with reflective capacitive outputcharacteristics and not transmitting pen state information. For example,and with reference to flowchart 400 of FIG. 4 , communication decisionmodule 206 determines that touch sensitive device 110 is not enabled toreceive pen state information 108 at step 406. Note that at step 406,that steps 402 and 404 have already been performed, which meanscommunication decision module 206 likewise determined that the sensitivedevice 110 is not enabled to perform two-way communication withadaptable digital pen 102 via first communication interface 202.Likewise, when communication decision module 206 determines that theattempt to establish two-way communication with touch sensitive device110 through second communication interface 204 was not successful,communication decision module 206 likewise implicitly determines thatone-way communication of pen state information 108 from adaptabledigital pen 102 to touch sensitive device 110 is not possible.Accordingly, because embodiments have failed to establish either one-wayor two-way communication between adaptable digital pen 102 and touchsensitive device 110 via first communication interface 202, and becauseembodiments have failed to establish communication via secondcommunication interface 204, it is not possible for embodiments ofadaptable digital pen 102 to communicate pen state information 108 totouch sensitive device 110 by any means whatsoever. In this instance,embodiments of communication decision module 206 operate tip electrode114 of adaptable digital pen 102 with reflective capacitive outputcharacteristics.

As discussed above, embodiments of adaptable digital pen 102 may beconfigured to attempt to determine an operating mode for adaptabledigital pen 102 that may be compatible with any touch sensitive devicewithout regard for the particular make and model of the touch sensitivedevice. Embodiments of touch sensitive device 110 may likewise beenabled to operate in various modes appropriate to a digital pen orother input method being employed by the user and may comprise varioushardware for such operation.

For example, FIG. 3 shows touch sensitive device 110, according to anexample embodiment. Touch sensitive device 110 includes hardware 304.Hardware 304 includes a touchscreen 306 which itself includes digitizer104. Digitizer 104 includes digitizer communication interface 308.Hardware 304 also includes a central processing unit (CPU) 310, arandom-access memory (RAM) 312 and input/output (I/O) module 314. I/Omodule 314 includes alternate communication interface 316. Touchsensitive device 110 further includes software 320 that may be loadedinto RAM 312 and accessed therefrom for execution by CPU 310 of hardware304. Software 320 includes an operating system 322 on which is executinga device driver 326 and a host application 324.

In an embodiment, hardware 304 of touch sensitive device 110 includestouchscreen 306. In FIG. 3 , digitizer 104 is depicted as beingintegrated into touchscreen 306. Such a configuration is exemplary only,and in other embodiments, touch sensitive device 110 may include aseparate digitizer 104 that is not integrated into a touch screen. Forexample, touch sensitive device 110 may comprise a touchpad, trackpad,graphics pad, graphics tablet, drawing tablet, drawing pad, pen tablet,digital art board, or other types of similar touch sensitive devicescapable of being used with adaptable pen 102 for capturing handwritingor drawings, and the like. Such embodiments of touch sensitive device110 will not typically include a display or have digitizer 104integrated into a touch screen.

Digitizer 104 as depicted in FIG. 3 also includes digitizercommunication interface 308 enabled to communicate with adaptabledigital pen 102 via first communication interface 202 as shown in FIG. 2. In embodiments, the type and manner of operation of digitizercommunication interface 308 is identical to that described above inrelation to first communication interface 202 of adaptable digital pen102.

CPU 310 of hardware 304 may be coupled to RAM 312 and I/O module 314 indigitizer 104 of touchscreen 306, either directly or through I/O module314. In an embodiment, touch input 318, generated at digitizer 104 maybe provided to I/O module 314. Touch input 318 may comprise the touchinputs detected by digitizer 104 in response to user interactions withtouch sensitive device 110 (whether with adaptable digital pen 102 orother input devices). In embodiments, touch input 318 may also includepen state information 108 received from adaptable digital pen 102 bydigitizer 104 as discussed above.

I/O module 314 may include any of several types of bus structures,including a memory bus or memory controller, a peripheral bus coupledto, for example, digitizer 104 of touchscreen 306, an acceleratedgraphics port, and a processor or local bus coupling CPU 310 with RAM312. Touch input 318 may initially be processed by operating system 322of software 320 through device driver 326 that may be configured toaccept touch input 318 from I/O module 314. In an embodiment, devicedriver 326 may be configured to further process or filter touch input318 prior to providing same to host application 324.

In an embodiment, I/O module 314 also includes alternate communicationinterface 316 enabled to communicate with adaptable digital pen 102 viasecond communication interface 204 as shown in FIG. 2 . In embodiments,the type and manner of operation of alternate communication interface316 is identical to that described above in relation to secondcommunication interface 204 of adaptable digital pen 102.

Note that foregoing general description of touch sensitive device 110 isprovided for illustration only, and embodiments of touch sensitivedevice 110 may comprise different hardware and/or software and mayoperate in manners different than described above. A description of anembodiment of touch sensitive device 110 in operation will now bediscussed in conjunction with the discussion of flowchart 700 of FIG. 7. The description of touch sensitive device 110 herein below makesexpress reference to adaptable digital pen 102 as depicted in FIGS. 1and 2 . It should be understood, however, that the discussed operationof embodiments of touch sensitive device 110 does not depend on theability of adaptable digital pen 102 to adapt its functioning asdiscussed above in relation to flowcharts 400 through 600. Instead, theoperation of touch sensitive device 110 described herein below, may beperformed in conjunction with any type of digital pen.

Embodiments of touch sensitive device 110 of FIG. 3 may operate invarious ways to adaptively switch operating modes to accommodatedifferent types of digital pens, such as, for example, adaptable digitalpen 102. For instance, FIG. 7 shows a flowchart 700 of a process fordetermining whether to operate touch sensitive device 110 with a digitalpen in a first mode or second mode, according to an embodiment.Flowchart 700 is described with continued reference to FIG. 3 . However,other structural and operational embodiments will be apparent to personsskilled in the relevant art(s) based on the following discussionregarding flowchart 700 and touch sensitive device 110 of FIG. 3 .

Flowchart 700 begins with step 702. Step 702 determines whether thetouch sensitive device is receiving pen state information from thedigital pen via a first communication channel while operating the touchsensitive device in a first mode. In an embodiment, touch sensitivedevice 110 may be configured to operate in a first mode, and determinewhether pen state information 108 is being received from adaptabledigital pen 102 via the communication channel associated with digitizercommunication interface 308. For example, touch sensitive device 110 maydetermine pen state information 108 is being received by detecting validpen state data on digitizer communication interface 308 according to anactive pen protocol.

Flowchart 700 continues with step 704. At step 704, and in response todetermining that the touch sensitive device is receiving pen stateinformation from the digital pen via the first communication channel,the touch sensitive device will continue to operate in the first mode.For example, when touch sensitive device 110 determines that it isreceiving pen state information 108 on digitizer communication interface308 while operating in the first mode, touch sensitive device 110 willcontinue to operate in the first mode. In an embodiment, touch sensitivedevice 110 will continue to operate in the first mode until it stopsreceiving valid pen state information 108 on digitizer communicationinterface 308.

Flowchart 700 continues with step 706. At step 706, and in response todetermining that the touch sensitive device is not receiving the penstate information via the first communication channel, touch sensitivedevice is switched to operate in a second mode and determines whetherthe touch sensitive device is enabled to receive the pen stateinformation from the digital pen via a second communication channel. Forexample, touch sensitive device 110 may be configured to switch touchsensitive device 110 to operate in a second mode, and to determinewhether touch sensitive device 110 is enabled to receive pen stateinformation 108 from adaptable digital pen 102 via the communicationchannel associated with alternate communication interface 316 of FIG. 3. In an embodiment, touch sensitive device 110 may be configured tooperate in a second mode, whereby pen state information 108 may bereceived using alternate communication interface 316 as shown in FIG. 3.

Flowchart 700 continues with step 708. At step 708, and in response todetermining that the touch sensitive device is enabled to receive thepen state information via the second communication channel, the touchsensitive device continues to operate the touch sensitive device in thesecond mode. For example, when touch sensitive device 110 determinesthat it is enabled to receive pen state information 108 while operatingin the second mode, touch sensitive device 110 will continue to operatein the second mode since operating in the second mode will suffice forreceiving pen state information 108 from adaptable digital pen 102. Inembodiments, touch sensitive device 110 will continue to operate in thesecond mode for as long as it continues to receive valid pen stateinformation 108 from adaptable digital pen 102.

In the foregoing discussion of steps 702-708 of flowchart 700, it shouldalso be understood that at times, such steps may be performed in adifferent order or even contemporaneously with other steps. For example,in embodiments, steps 702 and 704 pertaining to operating in a firstmode, steps 706 and 708 pertaining to operating in a second mode couldbe done in the reverse order. Likewise, determining whether touchsensitive device 110 is receiving pen state information, or is enabledto receive such information, via first or second communication channels,respectively, as performed in steps 702 and 706, may be performedsimultaneously in some embodiments. Other operational embodiments willbe apparent to persons skilled in the relevant art(s).

As discussed above, touch sensitive devices may receive pen stateinformation from adaptable digital pen 102 via a first communicationchannel in different ways, and embodiments of touch sensitive device 110may be configured to determine the proper manner in which to do so. Forexample, FIG. 8 shows a flowchart 800 of a process for determiningwhether a touch sensitive device is receiving pen state information froma digital pen via a first communication channel while operating thetouch sensitive device in a first mode, according to an embodiment.Flowchart 800 is described with continued reference to FIG. 3 . However,other structural and operational embodiments will be apparent to personsskilled in the relevant art(s) based on the following discussionregarding flowchart 800 and touch sensitive device 110 of FIG. 3 .

Flowchart 800 begins with step 802. In step 802, an attempt is made toestablish two-way communication with a digital pen through a firstcommunication channel while operating a touch sensitive device in afirst mode, and when the attempt is successful, the touch sensitivedevice receives the pen state information from the digital pen via thefirst communication channel and continues to operate the touch sensitivedevice in the first mode. For example, embodiments of touch sensitivedevice 110 may be configured to determine whether touch sensitive device110 is receiving pen state information 108 from adaptable digital pen102 while operating in a first mode by attempting to establish two-waycommunication between adaptable digital pen 102 and touch sensitivedevice 110 via the communication channel associated with digitizercommunication interface 308 of FIG. 3 . More specifically, touchsensitive device 110 may be configured to operate in a first mode toattempt to establish two-way communication with adaptable digital pen102 via digitizer communication interface 308 by trying each of a numberof different active pen protocols to determine whether two-waycommunication may be established with any of them. Such an attempt issuccessful when touch sensitive device 110 successfully receives returncommunication from adaptable digital pen 102 via digitizer communicationinterface 308 and, as a result, embodiments of touch sensitive device110 continue to operate in the first mode.

Flowchart 800 continues with step 804. At step 804, when the attempt toestablish two-way communication with the digital pen through the firstcommunication channel is not successful, the touch sensitive devicedetermines whether it is receiving one-way communication of the penstate information from the digital pen via the first communicationchannel. For example, even though touch sensitive device 110 may nothave succeeded in establishing two-way communication with adaptabledigital pen 102 through digitizer communication interface 308 at step802, it may nevertheless be possible for embodiments of touch sensitivedevice 110 to establish one-way communication with touch sensitivedevice 110 through digitizer communication interface 308. After failingto establish two-way communication with adaptable digital pen 102,embodiments of touch sensitive device 110 will determine it is receivingone-way communication of pen state information 108 by detecting validpen state information on digitizer communication interface 308.

Flowchart 800 continues with step 806. At step 806, when it isdetermined that touch sensitive device is receiving one-waycommunication of the pen state information from the digital pen via thefirst communication channel, the touch sensitive device attempts toestablish two-way communication with the digital pen through the secondcommunication channel. For example, in response to determining at step804 that touch sensitive device 110 is receiving valid pen stateinformation 108 on digitizer communication interface 308, touchsensitive device 110 may attempt to establish two-way communication withadaptable digital pen 102 via alternate communication interface 316. Atwo-way communication channel via alternate communication interface 316is necessary for adaptable digital pen 102 to learn from touch sensitivedevice 110 that pen state information 108 sent by adaptable digital pen102 via first communication interface 202 is, in fact, being received bytouch sensitive device 110, and that adaptable digital pen 102 shouldcontinue to send pen state information 108 via first communicationinterface 202.

Flowchart 800 continues with step 808. At step 808, when the attempt toestablish two-way communication with the digital pen through the secondcommunication channel is successful, the touch sensitive device sends aconfirmation to the digital pen that the touch sensitive device isreceiving the pen state information transmitted by the digital pen viathe first communication channel and continues to operate the touchsensitive device in the first mode. For example, after successfullyestablishing two-way communication with adaptable digital pen 102through digitizer communication interface 308, embodiments of touchsensitive device 110 then communicate to adaptable digital pen 102 thattouch sensitive device 110 is, in fact, receiving pen state information108. Likewise, touch sensitive device 110 will thereafter continue tooperate in the first mode to receive pen state information 108 fromadaptable digital pen 102 while valid pen state information 108 is beingreceived.

In the foregoing discussion of steps 802-808 of flowchart 800, it shouldalso be understood that at times, such steps may be performed in adifferent order or even contemporaneously with other steps. Otheroperational embodiments will be apparent to persons skilled in therelevant art(s).

Of course, and as discussed above, it will not always be possible forembodiments of touch sensitive device 110 to establish communicationwith a digital pen in either the first mode or the second mode to enableit to receive pen state information from the digital pen. In suchinstances, embodiments may be configured to operate in a “generic” modethat may allow touch sensitive device 110 to function as an input devicehaving widely compatible operating characteristics. For example, FIG. 9shows a flowchart 900 of a process for determining that that a touchsensitive device cannot be configured to operate with a particulardigital pen in either a first or second mode, according to an exampleembodiment. Flowchart 900 is described with continued reference to FIG.2 . However, other structural and operational embodiments will beapparent to persons skilled in the relevant art(s) based on thefollowing discussion regarding flowchart 900 and adaptable digital pen102 of FIG. 2 .

Flowchart 900 begins with step 902. In step 902, when it is determinedthat the touch sensitive device is not enabled to receive the pen stateinformation via the second communication channel or when the attempt toestablish two-way communication with the digital pen through the secondcommunication channel is not successful, touch sensitive device willoperate in a third mode wherein the touch sensitive device is notenabled to accept pen state information. For example, touch sensitivedevice 110 may determine that it is not enabled to receive pen stateinformation 108 from adaptable digital pen 102 via digitizercommunication interface 308. Attempts by touch sensitive device 110 toestablish two-way communication with adaptable digital pen 102 maylikewise fail. In such instances, touch sensitive device 110 has nomeans by which to receive pen state information 108 from adaptabledigital pen 102, and touch sensitive device 110 will therefore switch toa third mode wherein touch sensitive device 110 is not enabled to acceptor process pen state information 108.

III. Example Computer System Implementation

First communication interface 202, second communication interface 204,communication decision module 206, CPU 310, RAM 312, I/O module 314,software 320, operating system 322, host application 324, device driver326 and flowcharts 400-900 may be implemented in hardware, or hardwarecombined with software and/or firmware. For example, first communicationinterface 202, second communication interface 204, communicationdecision module 206 and flowcharts 400, 500, 600, 700, 800 and/or 900may be implemented as computer program code/instructions configured tobe executed in one or more processors and stored in a computer readablestorage medium. Alternatively, first communication interface 202, secondcommunication interface 204, communication decision module 206 andflowcharts 400, 500, 600, 700, 800 and/or 900 may be implemented ashardware logic/electrical circuitry (e.g., electrical circuits comprisedof transistors, logic gates, operational amplifiers, one or moreapplication specific integrated circuits (ASICs), one or more fieldprogrammable gate arrays (FPGAs), etc.).

For instance, in an embodiment, one or more, in any combination, offirst communication interface 202, second communication interface 204,communication decision module 206, sensor(s) 106, CPU 310, RAM 312, I/Omodule 314, software 320, operating system 322, host application 324,device driver 326, and flowcharts 400, 500, 600, 700, 800 and/or 900 maybe implemented in a SoC. The SoC may include an integrated circuit chipthat includes one or more of a processor (e.g., a central processingunit (CPU), microcontroller, microprocessor, digital signal processor(DSP), etc.), memory, one or more communication interfaces, and/orfurther circuits, and may optionally execute received program codeand/or include embedded firmware to perform functions.

FIG. 10 depicts an exemplary implementation of a computing device 1000in which embodiments may be implemented. For example, mobile electronicdevice 102 may be implemented in one or more computing devices similarto computing device 1000 in stationary or mobile computer embodiments,including one or more features of computing device 1000 and/oralternative features. The description of computing device 1000 providedherein is provided for purposes of illustration, and is not intended tobe limiting. Embodiments may be implemented in further types of computersystems, as would be known to persons skilled in the relevant art(s).

As shown in FIG. 10 , computing device 1000 includes one or moreprocessors, referred to as processor circuit 1002, a system memory 1004,and a bus 1006 that couples various system components including systemmemory 1004 to processor circuit 1002. Processor circuit 1002 is anelectrical and/or optical circuit implemented in one or more physicalhardware electrical circuit device elements and/or integrated circuitdevices (semiconductor material chips or dies) as a central processingunit (CPU), a microcontroller, a microprocessor, and/or other physicalhardware processor circuit. Processor circuit 1002 may execute programcode stored in a computer readable medium, such as program code ofoperating system 1030, application programs 1032, other programs 1034,etc. Bus 1006 represents one or more of any of several types of busstructures, including a memory bus or memory controller, a peripheralbus, an accelerated graphics port, and a processor or local bus usingany of a variety of bus architectures. System memory 1004 includes readonly memory (ROM) 1008 and random access memory (RAM) 1010. A basicinput/output system 1012 (BIOS) is stored in ROM 1008.

Computing device 1000 also has one or more of the following drives: ahard disk drive 1014 for reading from and writing to a hard disk, amagnetic disk drive 1016 for reading from or writing to a removablemagnetic disk 1018, and an optical disk drive 1020 for reading from orwriting to a removable optical disk 1022 such as a CD ROM, DVD ROM, orother optical media. Hard disk drive 1014, magnetic disk drive 1016, andoptical disk drive 1020 are connected to bus 1006 by a hard disk driveinterface 1024, a magnetic disk drive interface 1026, and an opticaldrive interface 1028, respectively. The drives and their associatedcomputer-readable media provide nonvolatile storage of computer-readableinstructions, data structures, program modules and other data for thecomputer. Although a hard dis, a removable magnetic disk and a removableoptical disk are described, other types of hardware-basedcomputer-readable storage media can be used to store data, such as flashmemory cards, digital video disks, RAMs, ROMs, and other hardwarestorage media.

A number of program modules may be stored on the hard disk, magneticdisk, optical disk, ROM, or RAM. These programs include operating system1030, one or more application programs 1032, other programs 1034, andprogram data 1036. Application programs 1032 or other programs 1034 mayinclude, for example, computer program logic (e.g., computer programcode or instructions) for implementing first communication interface202, second communication interface 204, communication decision module206, software 320, operating system 322, host application 324, devicedriver 326 and flowcharts 400, 500, 600, 700, 800 and/or 900 (includingany suitable step of flowcharts 400, 500, 600, 700, 800, and/or 900),and/or further embodiments described herein.

A user may enter commands and information into the computing device 1000through input devices such as keyboard 1038 and pointing device 1040.Other input devices (not shown) may include a microphone, joystick, gamepad, satellite dish, scanner, a touch sensitive and/or touch pad, avoice recognition system to receive voice input, a gesture recognitionsystem to receive gesture input, or the like. These and other inputdevices are often connected to processor circuit 1002 through a serialport interface 1042 that is coupled to bus 1006, but may be connected byother interfaces, such as a parallel port, game port, or a universalserial bus (USB).

A display screen 1044 is also connected to bus 1006 via an interface,such as a video adapter 1046. Display screen 1044 may be external to orincorporated in computing device 1000. Display screen 1044 may displayinformation, as well as being a user interface for receiving usercommands and/or other information (e.g., by touch, finger gestures,virtual keyboard, etc.). In addition to display screen 1044, computingdevice 1000 may include other peripheral output devices (not shown) suchas speakers and printers.

Computing device 1000 is connected to a network 1048 (e.g., theInternet) through an adaptor or network interface 1050, a modem 1052, orother means for establishing communications over the network. Modem1052, which may be internal or external, may be connected to bus 1006via serial port interface 1042, as shown in FIG. 10 , or may beconnected to bus 1006 using another interface type, including a parallelinterface.

As used herein, the terms “computer program medium,” “computer-readablemedium,” and “computer-readable storage medium” are used to refer tophysical hardware media such as the hard disk associated with hard diskdrive 1014, removable magnetic disk 1018, removable optical disk 1022,other physical hardware media such as RAMs, ROMs, flash memory cards,digital video disks, zip disks, MEMs, nanotechnology-based storagedevices, and further types of physical/tangible hardware storage media.Such computer-readable storage media are distinguished from andnon-overlapping with communication media (do not include communicationmedia). Communication media embodies computer-readable instructions,data structures, program modules or other data in a modulated datasignal such as a carrier wave. The term “modulated data signal” means asignal that has one or more of its characteristics set or changed insuch a manner as to encode information in the signal. By way of example,and not limitation, communication media includes wireless media such asacoustic, RF, infrared and other wireless media, as well as wired media.Embodiments are also directed to such communication media that areseparate and non-overlapping with embodiments directed tocomputer-readable storage media.

As noted above, computer programs and modules (including applicationprograms 1032 and other programs 1034) may be stored on the hard disk,magnetic disk, optical disk, ROM, RAM, or other hardware storage medium.Such computer programs may also be received via network interface 1050,serial port interface 1042, or any other interface type. Such computerprograms, when executed or loaded by an application, enable computingdevice 1000 to implement features of embodiments described herein.Accordingly, such computer programs represent controllers of thecomputing device 1000.

Embodiments are also directed to computer program products comprisingcomputer code or instructions stored on any computer-readable medium.Such computer program products include hard disk drives, optical diskdrives, memory device packages, portable memory sticks, memory cards,and other types of physical storage hardware.

IV. Additional Example Embodiments

A method of operating a digital pen that includes a pen tip withconfigurable output characteristics is described herein. The methodincludes: determining whether a touch sensitive device is enabled toreceive pen state information from the digital pen via a firstcommunication channel while operating the digital pen in a first mode;in response to determining that the touch sensitive device is enabled toreceive the pen state information via the first communication channel,continuing to operate the digital pen in the first mode; in response todetermining that the touch sensitive device is not enabled to receivethe pen state information via the first communication channel, switchingthe digital pen to operate in a second mode and determining whether thetouch sensitive device is enabled to receive the pen state informationfrom the digital pen via a second communication channel; and in responseto determining that the touch sensitive device is enabled to receive thepen state information via the second communication channel, continuingto operate the digital pen in the second mode.

In one embodiment of the foregoing method, determining whether the touchsensitive device is enabled to receive the pen state information fromthe digital pen via the first communication channel while operating thedigital pen in the first mode comprises: attempting to establish two-waycommunication with the touch sensitive device through the firstcommunication channel while operating the digital pen in the first mode,and when the attempt is successful, continuing to operate the digitalpen in the first mode; when the attempt to establish two-waycommunication with the touch sensitive device through the firstcommunication channel is not successful, attempting to establish two-waycommunication with the touch sensitive device through the secondcommunication channel; when the attempt to establish two-waycommunication with the touch sensitive device through the secondcommunication channel is successful, determining through the secondcommunication channel whether the touch sensitive device is enabled toreceive one-way communication of the pen state information from thedigital pen via the first communication channel; and when it isdetermined that the touch sensitive device is enabled to receive one-waycommunication of pen state information via the first communicationchannel, continuing to operate the digital pen in the first mode.

In one embodiment of the foregoing method, when it is determined thatthe touch sensitive device is not enabled to receive pen stateinformation via the second communication channel or when the attempt toestablish two-way communication with the touch sensitive device throughthe second communication channel is not successful, operating thedigital pen by operating the pen tip with reflective capacitive outputcharacteristics and not transmitting pen state information.

In one embodiment of the foregoing method, the first communicationchannel comprises an RF pen protocol communication channel between thedigital pen and a digitizer included in the touch sensitive device.

In one embodiment of the foregoing method, the second communicationchannel comprises a Bluetooth communication channel.

In one embodiment of the foregoing method, operating the digital pen inthe first mode comprises: operating the pen tip with active pen protocoloutput characteristics; intermittently collecting pen state information;and transmitting the collected pen state information to the touchsensitive device via the first communication channel.

In one embodiment of the foregoing method, operating the digital pen inthe second mode comprises: operating the pen tip with reflectivecapacitive output characteristics; intermittently collecting pen stateinformation; and transmitting the collected pen state information to thetouch sensitive device using the second communication channel.

In one embodiment of the foregoing method, the pen state informationcomprises at least one of: information derived from the pressure sensor,pen identifier (ID) information, timestamp information, tilt angleinformation, information based on a state of at least one inertialsensor, or information based on a state of at least one button of thedigital pen.

A method of operating touch sensitive device to receive digital peninput and provide same to a host application executing on the touchsensitive device, the digital pen including a pen tip with configurableoutput characteristics, is described herein. The method includes:determining whether the touch sensitive device is receiving pen stateinformation from the digital pen via a first communication channel whileoperating the touch sensitive device in a first mode; in response todetermining that the touch sensitive device is receiving pen stateinformation from the digital pen via the first communication channel,continuing to operate the touch sensitive device in the first mode; inresponse to determining that the touch sensitive device is not receivingthe pen state information via the first communication channel, switchingthe touch sensitive device to operate in a second mode and determiningwhether the touch sensitive device is enabled to receive the pen stateinformation from the digital pen via a second communication channel; andin response to determining that the touch sensitive device is enabled toreceive the pen state information via the second communication channel,continuing to operate the touch sensitive device in the second mode.

In one embodiment of the foregoing method, determining whether the touchsensitive device is receiving the pen state information from the digitalpen via the first communication channel while operating the touchsensitive device in the first mode comprises: attempting to establishtwo-way communication with the digital pen through the firstcommunication channel while operating the touch sensitive device in thefirst mode, and when the attempt is successful, receiving the pen stateinformation from the digital pen via the first communication channel andcontinuing to operate the touch sensitive device in the first mode; whenthe attempt to establish two-way communication with the digital penthrough the first communication channel is not successful, determiningwhether the touch sensitive device is receiving one-way communication ofthe pen state information from the digital pen via the firstcommunication channel; when it is determined that touch sensitive deviceis receiving one-way communication of the pen state information from thedigital pen via the first communication channel, attempting to establishtwo-way communication with the digital pen through the secondcommunication channel; when the attempt to establish two-waycommunication with the digital pen through the second communicationchannel is successful, sending a confirmation to the digital pen thatthe touch sensitive device is receiving the pen state informationtransmitted by the digital pen via the first communication channel, andcontinuing to operate the touch sensitive device in the first mode.

In one embodiment of the foregoing method, when it is determined thatthe touch sensitive device is not enabled to receive the pen stateinformation via the second communication channel or when the attempt toestablish two-way communication with the digital pen through the secondcommunication channel is not successful, operating the touch sensitivedevice in a third mode wherein the touch sensitive device is not enabledto accept pen state information.

In one embodiment of the foregoing method, the first communicationchannel comprises an RF pen protocol communication channel between thedigital pen and a digitizer included in the touch sensitive device.

In one embodiment of the foregoing method, the second communicationchannel comprises a Bluetooth communication channel.

In one embodiment of the foregoing method, operating the touch sensitivedevice in the first mode comprises: operating the digitizer according toan active pen protocol that detects pen tip position and receives penstate information via the first communication channel; providing thedetected pen tip position and pen state information to the hostapplication.

In one embodiment of the foregoing method, operating the touch sensitivedevice in the second mode comprises: operating the digitizer to accepttouch input via a capacitive sensor; receiving pen state information viathe second communication channel; correlating the received pen stateinformation with the touch input to determine pen tip position;providing the determined pen tip position and pen state information tothe host application.

In one embodiment of the foregoing method, pen state informationcomprises at least one of: information derived from a pressure sensor,pen identifier (ID) information, timestamp information, tilt angleinformation, information based on a state at least one inertial sensor,or information based on a state of at least one button of the digitalpen.

A digital pen is described herein. The digital pen includes: a shaft; apen tip including a tip electrode with configurable outputcharacteristics and disposed along a longitudinal axis at a first end ofthe shaft; a pressure sensor disposed proximate the pen tip; a firstcommunication interface enabled to communicate with a touch sensitivedevice via a first communication channel; a second communicationinterface enabled to communicate with the touch sensitive device via asecond communication channel; and a communication decision moduledisposed within the shaft and coupled to the tip electrode, the pressuresensor, the first communication interface and the second communicationinterface, the communication decision module configured to: determinewhether the touch sensitive device is enabled to receive pen stateinformation from the digital pen via the first communication channelwhile operating the digital pen in a first mode; in response todetermining that the touch sensitive device is enabled to receive thepen state information via the first communication channel, continue tooperate the digital pen in the first mode; in response to determiningthat the touch sensitive device is not enabled to receive the pen stateinformation via the first communication channel, switch the digital pento operate in a second mode and determine whether the touch sensitivedevice is enabled to receive the pen state information from the digitalpen via the second communication channel while operating in the secondmode; and in response to determining that the touch sensitive device isenabled to receive the pen state information via the secondcommunication channel, continue to operate the digital pen in the secondmode.

In one embodiment of the foregoing digital pen, operating the digitalpen in the first mode comprises: operating the tip electrode with activepen protocol output characteristics; intermittently collecting pen stateinformation; and transmitting the collected pen state information to thetouch sensitive device via the first communication channel.

In one embodiment of the foregoing digital pen, operating the digitalpen in the second mode comprises: operating the tip electrode withreflective capacitive output characteristics; intermittently collectingpen state information; and transmitting the collected pen stateinformation to the touch sensitive device via the second communicationchannel.

In one embodiment of the foregoing digital pen, pen state informationcomprises at least one of: information derived from a pressure sensor,pen identifier (ID) information, timestamp information, tilt angleinformation, information based on a state at least one inertial sensor,or information based on a state of at least one button of the digitalpen.

V. Conclusion

While various embodiments of the present invention have been describedabove, it should be understood that they have been presented by way ofexample only, and not limitation. It will be understood by those skilledin the relevant art(s) that various changes in form and details may bemade therein without departing from the spirit and scope of theinvention as defined in the appended claims. Accordingly, the breadthand scope of the present invention should not be limited by any of theabove-described exemplary embodiments but should be defined only inaccordance with the following claims and their equivalents.

What is claimed is:
 1. A method of operating a touch sensitive device toreceive digital pen input and provide same to a host applicationexecuting on the touch sensitive device, the digital pen including a pentip with configurable output characteristics, the method comprising:determining whether the touch sensitive device is receiving pen stateinformation from the digital pen via a first communication channel whileoperating the touch sensitive device in a first mode; in response todetermining that the touch sensitive device is receiving pen stateinformation from the digital pen via the first communication channel,continuing to operate the touch sensitive device in the first mode; inresponse to determining that the touch sensitive device is not receivingthe pen state information via the first communication channel, switchingthe touch sensitive device to operate in a second mode and determiningwhether the touch sensitive device is enabled to receive the pen stateinformation from the digital pen via a second communication channel; inresponse to determining that the touch sensitive device is enabled toreceive the pen state information via the second communication channel,continuing to operate the touch sensitive device in the second mode; andwhen it is determined that the touch sensitive device is not enabled toreceive the pen state information via the second communication channel,switching the touch sensitive device to operate in a third mode.
 2. Themethod of claim 1, wherein determining whether the touch sensitivedevice is receiving the pen state information from the digital pen viathe first communication channel while operating the touch sensitivedevice in the first mode comprises: attempting to establish two-waycommunication with the digital pen through the first communicationchannel while operating the touch sensitive device in the first mode,and when the attempt is successful, receiving the pen state informationfrom the digital pen via the first communication channel and continuingto operate the touch sensitive device in the first mode; when theattempt to establish two-way communication with the digital pen throughthe first communication channel is not successful, determining whetherthe touch sensitive device is receiving one-way communication of the penstate information from the digital pen via the first communicationchannel; when it is determined that touch sensitive device is receivingone-way communication of the pen state information from the digital penvia the first communication channel, attempting to establish two-waycommunication with the digital pen through the second communicationchannel; when the attempt to establish two-way communication with thedigital pen through the second communication channel is successful,sending a confirmation to the digital pen that the touch sensitivedevice is receiving the pen state information transmitted by the digitalpen via the first communication channel, and continuing to operate thetouch sensitive device in the first mode.
 3. The method of claim 1,wherein operating the touch sensitive device in a third mode comprisesoperating the touch sensitive device in a third mode wherein the touchsensitive device is not enabled to accept pen state information.
 4. Themethod of claim 1, wherein the first communication channel comprises anRF pen protocol communication channel between the digital pen and adigitizer included in the touch sensitive device.
 5. The method of claim4, wherein the second communication channel comprises a Bluetoothcommunication channel.
 6. The method of claim 1, wherein operating thetouch sensitive device in the first mode comprises: operating thedigitizer according to an active pen protocol that detects pen tipposition and receives pen state information via the first communicationchannel; and providing the detected pen tip position and pen stateinformation to the host application.
 7. The method of claim 1, whereinoperating the touch sensitive device in the second mode comprises:operating the digitizer to accept touch input via a capacitive sensor;receiving pen state information via the second communication channel;correlating the received pen state information with the touch input todetermine pen tip position; and providing the determined pen tipposition and pen state information to the host application.
 8. Themethod of claim 1, wherein the pen state information comprises at leastone of: information derived from a pressure sensor, pen identifier (ID)information, timestamp information, tilt angle information, informationbased on a state at least one inertial sensor, or information based on astate of at least one button of the digital pen.
 9. A touch sensitivedevice configured to receive digital pen input and provide same to ahost application executing on the touch sensitive device, the digitalpen including a pen tip with configurable output characteristics, thetouch sensitive device comprising: a digitizer including a firstcommunication channel; an input/output module including a secondcommunication channel; one or more processor circuits; one or morememory devices connected to the one or more processor circuits, the oneor more memory devices storing computer program logic recorded thereonthat when executed by the one or more processor circuits, causes the oneor more processor circuits to perform operations, the operationscomprising: determining whether the touch sensitive device is receivingpen state information from the digital pen via the first communicationchannel while operating the touch sensitive device in a first mode; inresponse to determining that the touch sensitive device is receiving penstate information from the digital pen via the first communicationchannel, continuing to operate the touch sensitive device in the firstmode; in response to determining that the touch sensitive device is notreceiving the pen state information via the first communication channel,switching the touch sensitive device to operate in a second mode anddetermining whether the touch sensitive device is enabled to receive thepen state information from the digital pen via the second communicationchannel; in response to determining that the touch sensitive device isenabled to receive the pen state information via the secondcommunication channel, continuing to operate the touch sensitive devicein the second mode; and when it is determined that the touch sensitivedevice is not enabled to receive the pen state information via thesecond communication channel, switching the touch sensitive device tooperate in a third mode.
 10. The touch sensitive device of claim 9,wherein determining whether the touch sensitive device is receiving thepen state information from the digital pen via the first communicationchannel while operating the touch sensitive device in the first modecomprises: attempting to establish two-way communication with thedigital pen through the first communication channel while operating thetouch sensitive device in the first mode, and when the attempt issuccessful, receiving the pen state information from the digital pen viathe first communication channel and continuing to operate the touchsensitive device in the first mode; when the attempt to establishtwo-way communication with the digital pen through the firstcommunication channel is not successful, determining whether the touchsensitive device is receiving one-way communication of the pen stateinformation from the digital pen via the first communication channel;when it is determined that touch sensitive device is receiving one-waycommunication of the pen state information from the digital pen via thefirst communication channel, attempting to establish two-waycommunication with the digital pen through the second communicationchannel; when the attempt to establish two-way communication with thedigital pen through the second communication channel is successful,sending a confirmation to the digital pen that the touch sensitivedevice is receiving the pen state information transmitted by the digitalpen via the first communication channel, and continuing to operate thetouch sensitive device in the first mode.
 11. The touch sensitive deviceof claim 9, wherein operating the touch sensitive device in a third modecomprises operating the touch sensitive device in a third mode whereinthe touch sensitive device is not enabled to accept pen stateinformation.
 12. The touch sensitive device of claim 9, wherein thefirst communication channel comprises an RF pen protocol communicationchannel between the digital pen and the digitizer.
 13. The touchsensitive device of claim 12, wherein the second communication channelcomprises a Bluetooth communication channel.
 14. A computer programproduct comprising a computer-readable memory device having computerprogram logic recorded thereon that when executed by at least oneprocessor of a computing device causes the at least one processor toperform operations, the operations comprising: determining whether atouch sensitive device is receiving pen state information from a digitalpen via a first communication channel while operating the touchsensitive device in a first mode; in response to determining that thetouch sensitive device is receiving pen state information from thedigital pen via the first communication channel, continuing to operatethe touch sensitive device in the first mode; in response to determiningthat the touch sensitive device is not receiving the pen stateinformation via the first communication channel, switching the touchsensitive device to operate in a second mode and determining whether thetouch sensitive device is enabled to receive the pen state informationfrom the digital pen via a second communication channel; in response todetermining that the touch sensitive device is enabled to receive thepen state information via the second communication channel, continuingto operate the touch sensitive device in the second mode; and when it isdetermined that the touch sensitive device is not enabled to receive thepen state information via the second communication channel, switchingthe touch sensitive device to operate in a third mode.
 15. The computerprogram product of claim 14, wherein determining whether the touchsensitive device is receiving the pen state information from the digitalpen via the first communication channel while operating the touchsensitive device in the first mode comprises: attempting to establishtwo-way communication with the digital pen through the firstcommunication channel while operating the touch sensitive device in thefirst mode, and when the attempt is successful, receiving the pen stateinformation from the digital pen via the first communication channel andcontinuing to operate the touch sensitive device in the first mode; whenthe attempt to establish two-way communication with the digital penthrough the first communication channel is not successful, determiningwhether the touch sensitive device is receiving one-way communication ofthe pen state information from the digital pen via the firstcommunication channel; when it is determined that touch sensitive deviceis receiving one-way communication of the pen state information from thedigital pen via the first communication channel, attempting to establishtwo-way communication with the digital pen through the secondcommunication channel; when the attempt to establish two-waycommunication with the digital pen through the second communicationchannel is successful, sending a confirmation to the digital pen thatthe touch sensitive device is receiving the pen state informationtransmitted by the digital pen via the first communication channel, andcontinuing to operate the touch sensitive device in the first mode. 16.The computer program product of claim 14, wherein operating the touchsensitive device in a third mode comprises operating the touch sensitivedevice in a third mode wherein the touch sensitive device is not enabledto accept pen state information.
 17. The computer program product ofclaim 14, wherein the first communication channel comprises an RF penprotocol communication channel between the digital pen and a digitizerincluded in the touch sensitive device.
 18. The computer program productof claim 17, wherein the second communication channel comprises aBluetooth communication channel.
 19. The computer program product ofclaim 14, wherein operating the touch sensitive device in the first modecomprises: operating the digitizer according to an active pen protocolthat detects pen tip position and receives pen state information via thefirst communication channel; and providing the detected pen tip positionand pen state information to the host application.
 20. The computerprogram product of claim 14, wherein operating the touch sensitivedevice in the second mode comprises: operating the digitizer to accepttouch input via a capacitive sensor; receiving pen state information viathe second communication channel; correlating the received pen stateinformation with the touch input to determine pen tip position; andproviding the determined pen tip position and pen state information tothe host application.